.bg{
    background: url('../../image/food.jpg');
    /* opacity: 0.5; */
    height: 100%;
}
.tips{
    width: 100%;
    position: absolute;
    background: rgba(0, 0, 0, 0.3);
    font-size: 40px;
    height: 300px;
    color: white;
    top:calc((100% - 300px)/2);
    text-align: center;
    display: flex;
    flex-direction: column;
    justify-content: space-around;
}